Text messaging has become a very popular mode of communication in many wireless communication networks. One example of text messaging is Short Message Service (SMS), which is a set of communication protocols allowing the exchange of short text messages (i.e., 160 characters or less) between mobile devices. While the term “text message” traditionally referred to text-only messages sent using SMS, it has been extended to include multimedia messages, such as images, video, sound content, etc. The multimedia messages may be sent using Multimedia Message Service (MMS) protocol. Often times, mobile users more frequently use text messaging for communication than voice calls.
A sender of a new text message enters one or more intended destinations for the message in a user device (e.g., a phone), and also enters the content of the message. The user device of the sender formats the text message into the proper protocol, and sends the text message to a message center in the network over the appropriate signaling channels. One example of a typical message center is an SMS Center (SMSC). The SMSC then attempts to deliver the SMS message to its destination(s).
Many traditional mobile (wireless) networks are circuit-switched. For example, GSM (Global Systems for Mobile Communications) networks and CDMA2000 networks are types of circuit-switched networks. Network operators offer text messaging services over these types of circuit-switched networks. Other types of networks gaining popularity are packet-switched networks. IP Multimedia Subsystem (IMS) networks and Long Term Evolution (LTE) networks are two examples of packet-switched networks. Network operators are attempting to offer text messaging services over these types of networks also.
One type of signaling protocol used in packet-switched networks is Session Initiation Protocol (SIP). When sending a text message, the data for the text message is encapsulated in a SIP request, which is typically a SIP MESSAGE. The SIP request is then routed to the recipient, where an application in the recipient's device attempts to parse the text message included in the SIP request.
The technical specifications of the 3rd Generation Partnership Project (3GPP and 3GPP2) have defined how text messages are exchanged over packet-switched (IP) networks. As part of these specifications, when a text message is delivered to a recipient, the recipient has to initiate a new SIP transaction to report back on the delivery success/failure of the text message. This methodology may cause problems in packet-switched networks when network operators attempt to offer text messaging to their customers.